Tapa

Background

TAPA is an acronym for Turkish Art Paint, and was developed by Serkan Yürekli for the 2007 Diogenes Internet Puzzle Solvers Club.

Puzzle and Goal

An unsolved puzzle consists of a rectangular grid, some of which contain one or more numbered clues.

The goal is to color some cells to satsify the clues.

Rules

The solved grid must satisfy the following conditions:

All black cells form a single orthogonally contiguous area.

Clues represent the number of black cells in adjacent cells. For instance, a clue of 2 1 means that there are two black cells together, then some white cells, then a single black cell, than some more white cells, in the eight (or five) adjacent cells.

Black cells cannot completely cover any 2x2 area.

Variants

Janko.at provides several variations, including using hexagons, having clues that represent mathematical differences, and so on.